Although they are nice visually, I am afraid the detail quality is not sufficient for a matte painting. The building in the second one is a bit weird architectonically speaking too, but who cares, right? :-D

The site looks good. The horizontal layout is funny, but could be a bit tricky for some to wrap their heads around it.
Anyway, I think you're on the right way. I liked the Rytmus music-video stuff.

Thanks for comment Pavel. Second one is not having enough details because it is more concept than finished matte and it is done in relatively low resolution. First one (jungle with transmitter) is finished in 6000px detailed on that resolution for print purposes.
Speaking of layout, i dont see anything much tricky about that...but i thing that is more question of taste. Lots of Photographers using this system these days and it working just fine. But im still working on some small improvements to increasing user experience.

Quite nice stuff in there. Just be careful of black levels and colors in the levels.
What I mean is, when you put a Levels on top of the all layers and move the mid-levels to right and left, you'll see the blacks, highlights and color differences. This is important when you, or client want to do something about that in comp.
Also there is too much grain in it, you can fake it with using Despeckle in Noise in Filters.

thanks Gerardo. That grain on city concept is actually added by me :) just to add more integrity to image since source photos and image itself was pretty low-res and i didnt want to repaint them for this image. btw. i think there is better solutions for grain removal than ones build in photoshop.

:) ok than, take the thingy back about the grain if you wanted to look like that :)
- yes I know there is better way, I just mention this because most of the people are using it and in some cases is just enough and if some baginners are reading this, they will have some TIP on this :)

here i am again with two latst works.
First one is matte paint for TV spot which actually turned in another direction during production:
Here you can see spot with final matte paint: http://vimeo.com/23533557
And here is first version of waterfall part.

Second project is matte paint of cover page for Technicall magazine.
Houses on left side are photography, rest is CGi.
Theme of this issue was "future traffic" As you can see, covr is inspired by Blade Runner which is my favorite movie. I always wanted to create futuristic version of Prague
and this was great opportunity to finally do it.
Here is website of magazine where you can see final cover: http://www.tecnicall.cz/